1. Field of the Invention
The present invention relates to a speed/position signal generator for outputting pulse signals of A and B, and Z phases corresponding to a frequency set value and a teeth number set value. "Teeth number" means the number of generated pulses per one rotation of a rotary encoder.
In brief, this generator electronically emulates the prior mechanical-type to phase incremental rotary encoder (two phase PG--that is, pulse generator) involving Z phase, which means that said generator statistically generates a signal corresponding to a rotation pulse of an electric motor.
2. Prior Art
When the rotation speeds of a plurality of electric motors are controlled, it is conventionally performed by controlling a deviation between a revolution speed of one electric motor (hereinafter referred to as a parent motor) among the plurality of electric motors and that of another electric motor (hereinafter referred to as a child motor) taking the revolution speed of the parent motor as a reference.
However, in such a construction there is a displacement of a mechanical rotary shaft of the parent motor, and a reference value produced owing to the error is transmitted to the child motor as it is. Further, any delay of signal transmission between the parent motor and the child motor makes highly accurate synchronization control difficult. This is undesirable for situations where a plurality of electric motors are operated.
In view of the difficulties with the prior art, it is an object of the present invention to provide a speed and position signal generator without any delay of signal transmission irrespective of mechanical error.